Oops. I responded to the wrong email. Looks like this has already been addressed. 73, Ken K3IU ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Ken K3IU wrote: > Mike: > From Release Notes > MCU 2.45 / DSP 1.92, 9-29-2008 > > * TRANSMIT NOISE GATE ADDED: The TX noise gate can be used to suppress > transmitted audio below a certain level, e.g. a noisy fan (not the one > on the K3, of > course). To use the noise gate, locate CONFIG:TX GATE, tap '1' to turn > it ON, > then use VFO A to set the desired threshold. Since there's no visual > indication that > transmit audio is below the threshold, you should adjust it using the > transmit voice > monitor (MON), ideally using headphones. Set the threshold high enough > to cut off > transmit audio due to shack noise, but not so high that it causes your > voice to drop > out too frequently. The TX GATE threshold can be adjusted in TX TEST mode. > > > > Mike Harris wrote: > >> G'day, >> >> Finally got around to making a replacement RS232 rig control cable using >> CAT6 patch cable, about three metres long. Method used was as detailed in >> the reference below. >> >> Results; spectacular! Noise on 6m increases approx 1dB when the cable is >> connected to the K3 (no antenna). Using the old cable the noise jumps up >> approx 9dB and was 6dB up on the noise floor when the antenna is >> connected. >> >> I can no longer hear the CRT monitor updating when the seconds tick over >> in WSJT. This was audible even when the old cable was disconnected from >> the K3 so it was probably being radiated from the cable and picked up by >> the antenna. >> >> Regards, >> >> Mike VP8NO >> >> ----- Original Message ----- >> From: "Jim Brown" <[email protected]> >> To: "Reflector Elecraft" <[email protected]> >> Sent: Thursday, April 23, 2009 10:10 AM >> Subject: Re: [Elecraft] RS232 Noise >> >> >> | On Wed, 22 Apr 2009 19:11:51 -0400, Mike Harris wrote: >> | >> | >This extra noise vanished when I removed the "RS232" cable from the >> | K3. >> | >The cable is actually the one I made up for the K2. >> | >> | There are several problems in the setup. First, the K3 connector shells >> | are not properly bonded to the chassis, so the cable shield is useless. >> | Second, the cable Elecraft sold with the K2-series products used >> | parallel conductors, not twisted pairs. That's a recipe for noise and >> | RFI. >> >> <snip> >> >> | 1) Build the serial cable shown in my RFI application note. >> | http://audiosystemsgroup.com/RFI-Ham.pdf It uses CAT5 cable. When VHF >> | noise is a concern, shielded CAT5 may offer further improvements. >> | >> | 3) Fix the pin 1 problem in the K3 by bonding the DB-connectors to the >> | chassis. Pin 1 problems couple RFI in both directions -- that is, they >> | let RF into equipment and they put RF onto cables that radiate it. >> | >> | 73, >> | >> | Jim Brown K9YC >> >> ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:[email protected] >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> >> >> > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected]
This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
